You have to pay in full to the developer. By taking out a loan which consists of a downpayment.
The developer now has 100% of the money. And the buyer has nothing but debt.
The developers are either never breaking ground or never completing the building. Using the money to buy more land and sell more homes.
When they file for bankruptcy. The banks still need the money back from the buyer. Since the buyer has no home because it was never finished they effectively lose their investment and their lives as debt collection takes their cars, live-in home. Etc.
Stop spreading misinformation that buyers aren’t suffering. This is people’s lives at stake. Lying to people and pretending like nothing is wrong makes you a terrible human being when people’s lives are at stake.
I'm sure you have a good point about mortgages and developers and banks, but it's more important not to set the forum on fire, and that is what the site guidelines exist to avoid.
If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.